Rewrite ${\dfrac{8^{-5}}{8^{-7}}}$ in the form ${8^n}$.
Solution: ${ \dfrac{8^{-5}}{8^{-7}} = 8^{-5-(-7)}} $ ${ \hphantom{\dfrac{8^{-5}}{8^{-7}}} = 8^{2}} $